If you setup that old WordPress blog as an integration with your bbPress installation and then install the bbPress-Post plugin from http://dev.mbzeus.net/forum/ you can do it. It is a real pain in the butt, but if you have the integration plugin working, you can ‘edit’ each of the old posts and then save them again . This creates the entry in bbPress. Last time I checked though, it didn’t update the timestamp to the original post time though.

Speaking of which, it doesn’t add a topic-slug either, which is required to have permalinks set to slug. I tried adding the topic_slug field and a variable to make it update, but when I did that it didn’t work at all Can someone else have a look at this too?